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subnet-overlap

v1.1.0

Published

Check if subnet overlapped.

Readme

subnet-overlap

npm version CI codecov semantic-release: conventionalcommits

NPM

Check if subnets overlap with existing subnets. Works in both Node.js and browser environments.

Installation

npm

npm install subnet-overlap

GitHub Packages

npm install @SangHakLee/subnet-overlap --registry=https://npm.pkg.github.com

Usage

Node.js

const subnetOverlap = require('subnet-overlap')

// Check if subnet overlaps with existing subnets
subnetOverlap(['172.22.2.0/24'], '172.22.2.0/24')  // true
subnetOverlap(['172.22.1.0/24'], '172.22.2.0/24')  // false

// Check against multiple existing subnets
subnetOverlap(
  ['10.0.0.0/24', '172.16.0.0/24', '192.168.0.0/24'],
  '172.16.0.128/25'
)  // true

TypeScript

import subnetOverlap from 'subnet-overlap'

const hasOverlap: boolean = subnetOverlap(['10.0.0.0/16'], '10.0.1.0/24')

Browser

<!-- unpkg -->
<script src="https://unpkg.com/subnet-overlap@latest/dist/browser/subnetOverlap.min.js"></script>

<!-- jsdelivr -->
<script src="https://cdn.jsdelivr.net/npm/subnet-overlap@latest/dist/browser/subnetOverlap.min.js"></script>

<script>
  console.log(subnetOverlap(['172.22.2.0/24'], '172.22.2.0/24'))  // true
  console.log(subnetOverlap(['172.22.1.0/24'], '172.22.2.0/24'))  // false
</script>

API

subnetOverlap(existedCidrs, nowCidr)

Returns true if nowCidr overlaps with any subnet in existedCidrs, false otherwise.

Parameters

  • existedCidrs Array<string> - Array of existing subnet CIDR notations
  • nowCidr string - The subnet CIDR notation to check

Returns

boolean - true if there is an overlap, false otherwise

Throws

  • TypeError - If existedCidrs is not an array or nowCidr is not a string

Documentation

Full API documentation is available at GitHub Pages.

Development

# Install dependencies
npm install

# Build TypeScript
npm run build

# Build browser bundle
npm run build:browser

# Run tests
npm test

# Run tests with coverage
npm run coverage

# Run ESLint
npm run lint

# Generate documentation
npm run typedoc

License

MIT © SangHakLee